(CNN) – A Republican National Committee event Monday commemorating the 1963 "March on Washington" took a political turn when a speaker called out African-American politicians he said are exploiting their posts for dishonest ends.

"We must be honest about those black politicians who are standing on those who sacrificed and are using that position for corrupt purposes," said social activist Bob Woodson Sr., the founder and president of the Center for Neighborhood Enterprise. "We need to call them out, because they are moral traitors. They are moral traitors. But we're silent about that."
Woodson's organization, based in Washington, helps neighborhoods solve problems like violence and lack of housing. Before founding the Center for Neighborhood Enterprise in 1981, Woodson – who is black - headed the National Urban League's Administration of Justice Division.

His remarks Monday came as national Republicans were marking a half-century since Martin Luther King Jr. delivered his "I Have a Dream" speech on the steps of the Lincoln Memorial in Washington. While a celebration will take place at the site of that speech Wednesday, no Republican politicians are slated to speak.

President Barack Obama, and former Presidents Bill Clinton and Jimmy Carter, will both make remarks. An invitation to former President George W. Bush was declined since the Republican is still recovering from a heart procedure earlier this month.

Other speakers at Monday's RNC event included chairman Reince Priebus and T.W. Shannon, the speaker of Oklahoma's state House of Representatives.

Also attending the event – Rep. Jim Sensenbrenner, the Wisconsin Republican who's been a leading GOP voice on rewriting portions of the Voting Rights Act after the Supreme Court gutted key provisions in June.

Saying the court had "thrown a monkey wrench" into the law, Sensenbrenner said it was lawmakers' responsibility to fix it by developing new guidelines for how the federal government can control states' voting laws.

But it was Woodson who delved most pointedly into politics, a fact he acknowledged when he apologized for being the "skunk at the garden party."

Woodson alleged during his ten minute address that the message of the civil rights movement was being diluted as the rights of other groups are being placed ahead of poor African-Americans.

"Blacks today, we're talking about the dream, for many the dream, for poor people, is a nightmare," he said. "Everybody has come in front of them on the bus. Gays, immigrants, women, environmentalists. We never hear any talk about the conditions confronting poor blacks and poor people in general."

He added that African-American leaders who decried the shooting death of Trayvon Martin, but not subsequent acts of violence, are failing to uphold King's message.

"If Dr. King were alive today, he would not just be talking about justice for Trayvon Martin, but he would also give a prayer for the 18-year-old man, for this little baby who was shot in the face by two black kids, or by the World War II veteran who was beaten to death for $50. Or the Oklahoma player who was killed. Dr. King, if anything, was morally consistent."